Hand-held power tool

ABSTRACT

The disclosure is based on a hand-held power tool having at least one switch device which comprises at least one switching element at least for activating a power supply of a drive unit, having at least one quick-change tool holder which is provided for holding an insertion tool which is different from an insertion tool with an SDS® shaft having a maximum transverse extent of 10 mm and/or having at least one accumulator interface. It is proposed that the at least one switching device comprises at least one locking unit which is provided for maintaining, at least essentially independently of an effect of an operator activation force, an active operating mode which can be activated by actuating the at least one switching element.

This application claims priority under 35 U.S.C. § 119 to applicationno. DE 10 2015 222 152.0, filed on Nov. 11, 2015 in Germany, thedisclosure of which is incorporated herein by reference in its entirety.

BACKGROUND

Hand-held power tools, in particular with an SDSplus® tool holder whichcomprise a switch-locking unit have already been proposed.

SUMMARY

The disclosure is based on a hand-held power tool having at least oneswitch device which comprises at least one switching element, at leastfor activating a power supply of a drive unit, having at least onequick-change tool holder which is provided for holding an insertion toolwhich is different from an insertion tool with an SDS® shaft having amaximum transverse extent of 10 mm and/or having at least oneaccumulator interface.

It is proposed that the at least one switching device comprises at leastone locking unit which is provided for maintaining, at least essentiallyindependently of an effect of an operator activation force, an activeoperating mode which can be activated by actuating the at least oneswitching element.

A “hand-held power tool” is intended in this context to refer, inparticular, to a portable machine which can process workpieces and isadvantageously a drilling machine, a hammer drill and/or percussionhammer, a saw, a plane, a screwdriver, a milling machine, a grindingmachine, an angle grinder, a garden implement and/or a multi-functionaltool, which can be transported by an operator in order to processworkpieces without the need for a transportation machine. The hand-heldpower tool has, in particular, a mass which is less than 40 kg,preferably less than 10 kg and particularly preferably less than 5 kg. A“switching element” is to be understood in this context as referring, inparticular, to an element or an assembly which is provided to beactuated directly at least partially by an operator of the hand-heldpower tool and which is provided to form and/or disconnect anelectrically conductive connection between at least two points, inparticular between at least two switching contacts of the switchingunit. The at least one switching unit is preferably formed at leastpartially as an electronic, mechanical and/or electromechanicalswitching unit which comprises, in particular, at least one relay.

A “drive unit” is to be understood in this context as referring, inparticular, to a unit which is provided for generating at least onedriving torque and for making it available to be passed on, inparticular, to an insertion tool. The drive unit preferably comprises anelectric motor. A “quick-change tool holder” is to be understood in thiscontext as referring, in particular, to a tool holder for detachablyfastening an insertion tool to the hand-held power tool which isdesigned to be capable of being operated in a tool-less fashion. Thequick-change tool holder is preferably provided for holding an insertiontool having a shaft which is associated with an insertion system, inparticular having an SDSmax® shaft. However, other embodiments of theinsertion tool shaft associated with an insertion system, which appearto be appropriate to a person skilled in the art are conceivable, theseembodiments being, for example, a round shaft, a square shaft, hexagonalshaft or an HEX shaft. The term SDS® is a registered trade mark ofRobert Bosch GmbH (registration number DE 396086497). The term“transverse extent” is to be understood in this context as referring, inparticular, to a dimension of the shaft of the insertion tool in a planewhich is arranged perpendicularly with respect to a longitudinaldirection of the insertion tool. A “shaft” is to be understood in thiscontext as referring, in particular, to a part of the insertion toolwhich is embodied so as to be at least essentially, preferablycompletely, free of a processing geometry, in particular of a cuttinggeometry. The shaft of the insertion tool is preferably provided forcoupling the insertion tool to the tool holder of the hand-held powertool.

The term “accumulator interface” is to be understood in this context asreferring, in particular, to a unit of the hand-held power tool which isprovided for electrically, and preferably in addition at least partiallymechanically, coupling the hand-held power tool to at least oneaccumulator, in particular to at least one hand-held power toolaccumulator pack. In a state in which the accumulator is coupled to theaccumulator interface it is provided to supply the hand-held power toolwith an operating voltage for operating at least the drive unit of thehand-held power tool.

The locking unit is preferably embodied at least partially in amechanical and/or electric or electronic fashion. The locking unit ispreferably provided for mechanically locking the at least one switchingelement. However, it is also conceivable for the locking unit to beprovided to maintain the active operating mode electronically,preferably independently of a position of the at least one switchingelement of the switching device, in particular by means of an open-and/or closed-loop control unit. In this context, the open-loop and/orclosed-loop control unit can be formed at least partially by anopen-loop and/or closed-loop control unit for performing open-loopand/or closed-loop control of the hand-held power tool or can beembodied separately from the open-loop and/or closed-loop control unitfor performing open-loop and/or closed-loop control of the hand-heldpower tool. The locking unit preferably comprises at least one lockingelement which is provided for activating the maintaining of the activeoperating mode. The at least one locking unit can advantageously beembodied as an actuating element for actuation by an operator, inparticular as an HMI (human machine interface) and/or in some other waywhich appears appropriate to a person skilled in the art. The lockingunit is preferably at least partially arranged in the region of the atleast one switching element of the switching device. The locking unit ispreferably provided for maintaining the active operating mode in achronologically unlimited fashion, in particular up to an activedeactivation of the active operating mode by an operator of thehand-held power tool and/or by means of at least one switch-off signalof an open- and/or closed-loop control unit. The deactivation by theoperator can be carried out, for example, by means of at least oneswitch-off element of the hand-held power tool which can be actuated bythe operator. The at least one switch-off element can preferably beembodied at least partially integrally with the at least one switchingelement of the switching unit. The term an “open-loop and/or closed-loopcontrol unit” is to be understood in this context as referring, inparticular, to a control unit having at least one open-loop controlelectronics which comprises, in particular, at least one processor unitand a memory unit as well an operating program which can be stored inthe memory unit.

The embodiment of the hand-held power tool according to the disclosurecan, in particular in the case of a relatively long-lasting workingprocess, advantageously facilitate handling of the hand-held power tooland permit preferably good working ergonomy for the operator andparticularly efficient working progress. In particular, an advantage interms of ergonomy for network-bound hand-held power tools can beobtained. In addition, the locking unit can permit a gripping positionto be changed without interruption of the process. This canadvantageously permit fatigue-free or low-fatigue working by theoperator with the hand-held power tool, in particular in the case ofbalancing and/or agitating.

If the hand-held power tool also comprises at least one double-sidedadditional handle, the hand-held power tool can preferably additionallybe used, for example, as a ground boring device, as result of which afield of application of the hand-held power tool can be advantageouslyextended.

In addition, it is proposed that the at least one locking unit has atleast one timer function which is provided for at least partiallyautomatically triggering the maintaining of an active operating mode asa function of an actuation period of the switching element. The timerfunction is provided, in particular, for automatically triggering themaintaining of an active operating mode after 5 seconds, preferablyafter 10 seconds and particularly preferably after 20 seconds ofuninterrupted actuation of the switching element by the operator.However, other time periods which appear appropriate to a person skilledin the art are also conceivable. The term “automatic” is to beunderstood in this context as meaning, in particular, at least virtuallyand preferably completely independently of an active intervention by theoperator. The timer function is preferably made available at leastpartially by control electronics. As result, advantageously simple andpreferably operator-friendly configuration of the at least one lockingunit can be achieved.

In addition, it is proposed that the at least one locking unit comprisesat least one acoustic pick-up element which is provided at least forpicking up at least one acoustic characteristic variable, wherein thelocking unit is provided for performing open-loop and/or closed-loopcontrol of the maintaining of an active operating mode as a function ofthe at least one picked up acoustic characteristic variable. An“acoustic characteristic variable” is to be understood in this contextas referring, in particular, to at least one sound signal which ispreferably in the frequency range between 16 Hz to 20 kHz which can beheard by humans and which is provided for transmitting at least one itemof information. The acoustic characteristic variable is preferablyformed from a speech command of the operator. The at least one acousticpick-up element is preferably formed from at least partially by amicrophone. As result, advantageously simple operation of the at leastone locking element, in particular by a voice-activated controller, canbe achieved.

Furthermore, it is proposed that the at least one locking unit comprisesat least one pick-up element for picking up a movement characteristicvariable of an operator, wherein the locking element is provided forperforming open-loop and/or closed-loop control of the maintaining of anactive operating mode as a function of the at least one picked upmovement characteristic variable. A “movement characteristic variable”is to be understood in this context as referring, in particular, to atleast one movement, in particular of the operator, preferably a handmovement of the operator which is provided at least for conveying atleast one item of information. The movement characteristic variable ispreferably formed by a gesture of the operator. The at least one pick-upelement is preferably formed at least partially by a camera. As aresult, an advantageously simple operator control process of the atleast one locking unit, in particular by means of gesture-based control,can be achieved.

In addition it is proposed that the hand-held power tool comprises atleast one sensor unit at least for picking up at least one safetycharacteristic variable in order to pick up a fault, wherein the lockingunit is provided for automatically switching off the drive unit as afunction of the picked up safety characteristic variable or for reducinga rotational speed and/or a power level of the drive unit. A “sensorunit” is to be understood as meaning, in particular, a unit which isprovided for recording at least one physical property, wherein therecording can take place actively such as, in particular, by generatingand emitting an electrical measurement signal, and/or passively, suchas, in particular, by picking up changes in properties of a sensorcomponent. Various sensor units which appear appropriate to a personskilled in the art are conceivable. The sensor unit can preferablycomprise at least one sensor element which can be embodied, for example,as an acceleration sensor, position sensor, gyroscope, temperaturesensor and/or in some other way which appears appropriate to a personskilled in the art. Alternatively or additionally, the at least onesensor element can also be embodied as a moisture sensor and/orconductivity sensor, in particular in a handle of the hand-held powertool, in order to detect that the hand-held power tool is being held inan operator's hand, in order to deactivate the maintaining of the activeoperating mode when the operator lets go of the tool.

A “safety characteristic variable” is to be understood in this contextas meaning, in particular, a value of a physical property which isrelevant at least to safe operation of the hand-held power tool, whichoperation is at least free of injury for an operator and at leastpartially free of damage for the hand-held power tool. The safetycharacteristic variable is preferably embodied as acceleration,temperature, in particular of the drive unit and/or of a percussionmechanism and/or as some other physical parameter which appearsappropriate to a person skilled in the art. The at least one sensor unitpreferably comprises at least one acceleration sensor for picking upblocking and/or dropping or a free fall of the hand-held power tool, atleast one current sensor for picking up blocking on the basis of highcurrents, at least one temperature sensor for picking up overheating ofa drive unit and/or the percussion mechanism of the hand-held power tooland/or at least one other sensor which appears appropriate to a personskilled in the art.

As result, a preferably high level of safety can be achieved for theoperator and/or for the hand-held power tool in an advantageouslyreliable way. In particular, a risk of injury in the event of blockingof an insertion tool during a drilling operation, during which thehand-held power tool would rotate in an uncontrolled fashion about amachining axis in an active operating mode can be advantageouslyreduced. In particular, in the case of a hand-held power tool with anaccumulator interface, the hand-held power tool could, in the event ofblocking in a locked state of the active operating mode without aprotection mechanism which the sensor unit makes available only bedeactivated by removing a hand-held power tool accumulator pack, whichwould constitute a large risk for the operator of the hand-held powertool.

In addition it is proposed that the hand-held power tool has at leastone sensor unit which has at least one pressure sensor for picking up atleast one pressing force, wherein the locking unit is provided formaintaining of an active operating mode as a function of the picked uppressing force. A “pressing force” is to be understood in this contextas meaning, in particular, a force with which an insertion tool which iscoupled to the hand-held power tool is pressed in an operating state bythe operator against a workpiece which is to be machined. The pressingsensor can preferably be coupled to a dead man's switch. The pressingforce detected by the pressure sensor is advantageously interrogatedcontinuously and without interruption. As result the hand-held powertool can preferably be prevented from being put down in an activeoperating mode.

Furthermore, it is proposed that the hand-held power tool comprises atleast one percussion mechanism and at least one sensor unit, wherein theat least one sensor unit comprises at least one frequency sensor whichis provided for picking up an impact frequency of the percussionmechanism, wherein the locking unit is provided for performing open-loopand/or closed-loop control of the maintaining of an active operatingmode as a function of the picked up impact frequency. In this context,“percussion mechanism” is to be understood as meaning, in particular, aunit which is provided for translating a rotational drive movement ofthe drive unit of the hand-held power tool at least partially into alinear movement of an impacting element of the percussion mechanism inorder to transmit at least one impact pulse to the insertion toolcoupled to the hand-held power tool. In this context, “impact frequency”is to be understood as meaning, in particular, a frequency of a periodiclinear movement of the impact element of the percussion mechanism in atleast one operating state. As result, operation of the hand-held powertool with idle strokes of the percussion mechanism can preferably beprevented.

In addition, it is proposed that the hand-held power tool comprises atleast one communication unit for communicating with at least oneexternal device, wherein the at least one locking unit is provided forperforming open-loop and/or closed-loop control of the maintaining of anactive operating mode as a function of a communication between the atleast one communication unit and the at least one external device. Theat least one external device is preferably formed by a Smartphone, atable, a cloud and/or some other, in particular, electrical orelectronic device which appears appropriate to a person skilled in theart. A “communication” is to be understood in this context as meaning,in particular, an at least unidirectional, preferably bidirectional,exchange of data and/or information at least between the at least oneexternal device and the at least one communication unit. The operatorcan preferably at least partially operate the at least one locking unitvia the at least one communication unit by means of the at least oneexternal device. The communication between the at least one externaldevice and the at least communication unit can preferably be carried outvia a wireless link, for example by means of radio, WLAN, Bluetooth, IRand/or by means of some other wireless link which appears appropriate toa person skilled in the art. However, a connection of the at least oneexternal device to the at least one communication unit via a cable isalso conceivable.

The communication unit can additionally be provided for the purpose ofwireless coupling of at least the locking unit and the sensor unitand/or of further components and/or assemblies which appear appropriateto a person skilled in the art. As result, preferably flexible andoperator-friendly operation of the locking unit of the hand-held powertool can be achieved.

In addition, a method is proposed for operating the hand-held power toolaccording to the disclosure having at least one method step in which anoperator activates an active operating mode by actuating at least oneswitching element, and having at least one further method step in whichat least one locking unit maintains the active operating modeindependently of the actuation of the at least one switching element bythe operator. As a result, particularly good relief for the operator andparticularly efficient working progress can be achieved in anadvantageously simple way, in particular in the case of a relativelylong lasting working process.

Furthermore, it is proposed that the method have at least one furthermethod step in which a fault is picked up and automatic deactivation ofthe active operating mode which is maintained by means of the lockingunit is carried out as a function of the picked up fault. A “fault” isto be understood in this context as meaning, in particular, that apredefined critical limiting value of at least one safety characteristicvariable of the hand-held power tool, in particular in an active state,is reached or exceeded. As result, a preferably high level of safety forthe operator and/or for the hand-held power tool can be achieved in aparticularly reliable fashion.

The hand-held power tool according to the disclosure is not intendedhere to be restricted to the application and embodiment described above.In particular, the hand-held power tool according to the disclosure canhave, for the purpose of carrying out a method of functioning asdescribed here, a number of individual elements, components and unitswhich differs from the number specified here. In addition, in the caseof the value ranges which are specified in this disclosure the valueswhich also lie within the specified limits are also to be considered asbeing disclosed and as being capable of being used as desired.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages can be found in the following description of thedrawings. The drawings illustrate a plurality of exemplary embodimentsof the disclosure. The drawings and the description contain numerousfeatures in combination. A person skilled in the art will alsoexpediently consider the features individually and combine them to formappropriate further combinations.

In the drawings:

FIG. 1 shows a hand-held power tool according to the disclosure in aschematic side view,

FIG. 2 shows a schematic illustration of a circuit of the hand-heldpower tool,

FIG. 3 shows an alternative configuration of a hand-held power toolaccording to the disclosure in a schematic side view,

FIG. 4 shows a schematic illustration of a circuit of the hand-heldpower tool which is configured in an alternative fashion,

FIG. 5 shows a further alternative configuration of a hand-held powertool according to the disclosure in a schematic side view,

FIG. 6 shows a schematic illustration of a circuit, configured in analternative fashion, of the hand-held power tool which is configured inan alternative fashion,

FIG. 7 shows a further alternative configuration of a hand-held powertool according to the disclosure in a schematic side view,

FIG. 8 shows a schematic illustration of a further circuit, configuredin an alternative fashion of the hand-held power tool which isconfigured in an alternative fashion, and

FIG. 9 shows a flowchart of a method relating to operation of thehand-held power tool according to the disclosure.

DETAILED DESCRIPTION

FIG. 1 shows a hand-held power tool 10 a having a tool holder 48 a. Thehand-held power tool 10 a is formed by a hammer drill. However, otherconfigurations of the hand-held power tool 10 a which appear to beappropriate to a person skilled in the art, such as, for example, as ahammer drill, drilling machine, hand-held jigsaw, hand-held circular sawor angle grinder are conceivable. The tool holder 48 a is provided forholding an insertion tool 20 a, which can be embodied as a drill and/orchisel. The tool holder 48 a is formed by a quick-change tool holder 18a. The quick-change tool holder 18 a is provided for holding theinsertion tool 20 a which is different from an insertion tool with anSDS® shaft with a maximum transverse extent of 10 mm. The quick-changetool holder 18 a is provided for holding the insertion tool 20 a whichhas an SDSmax® shaft. The quick-change tool holder 18 a is embodied asan SDSmax® quick-change tool holder. However, other configurations ofthe quick-change tool holder 18 a or of the shaft of the insertion tool20 a which appear appropriate to a person skilled in the art, such as,for example as part of an HEX quick-change system are conceivable,wherein a transverse extent of the shaft is, in particular, at least 20mm and at maximum 50 mm.

Furthermore, the hand-held power tool 10 a has at least one drive unit16 a. The hand-held power tool 10 a has a drive unit 16 a whichcomprises an electric motor 50 a. In addition, the hand-held power tool10 a has a transmission unit 52 a. The transmission unit 52 a has here aswitch-over unit (not illustrated in more detail) which is provided forswitching over between a rotating power take off, percussion power takeoff and rotating and percussion power take off (not illustrated indetail). A torque which is generated by the electric motor 50 a of thedrive unit 16 a is converted by the transmission unit 52 a into anoperating function which is illustrated by an operator, and is conductedto a power take off device 54 a, which has a percussion mechanism 34 a.The power take off device 54 a is connected directly to the tool holder48 a. The electric motor 50 a, the transmission unit 52 a and the powertake off device 54 a are enclosed by two housing shells 56 a of thehand-held power tool 10 a. Basically, configurations in which the unitsare arranged in two or more pot-like housing parts are also conceivable.The hand-held power tool 10 a also comprises a power cable 58 a which isprovided for connecting the hand-held power tool 10 a to a powernetwork, and for supplying the hand-held power tool 10 a with electricalenergy.

The hand-held power tool 10 a additionally has at least one switchdevice 12 a which comprises at least one switching element 14 a at leastfor activating a power supply of the drive unit 16 a (FIG. 2). Thehand-held power tool 10 a has a switch device 12 a which comprises aswitching element 14 a for activating the electric motor 50 a of thedrive unit 16 a. The switching element 14 a is embodied as a mechanicalswitching element. The switching element 14 a is formed by a pushbutton. However, other configurations of the switching element 14 awhich appear appropriate to a person skilled in the art, such as, forexample, at least partially as an electronic switching element or as atouchpad, are conceivable. The switching element 14 a is provided forclosing at least one electrical contact of a circuit for activating thepower supply of the drive unit 16 a. The switching element 14 a isembodied so as to be directly actuable by an operator. In order toactivate the electric motor 50 a of the drive unit 16 a, the operator ofthe hand-held power tool 10 a presses the switching element 14 a andtherefore places the hand-held power tool 10 a in an active operatingmode. In order to maintain this active operating mode, the operatorkeeps the switching element 14 a pressed.

The switching element 12 a also comprises at least one locking unit 24 awhich is provided at least essentially independently of an effect of anoperator actuation force for maintaining the active operating mode,which mode can be activated by actuating the switching element 14 a. Thelocking unit 24 a is embodied as an electronic locking unit. Thehand-held power tool 10 a additionally has at least an open-loop and/orclosed-loop control unit 60 a which is provided for performing open-loopand/or closed-loop control of at least the electric motor 50 of thedrive unit 16 a. The locking unit 24 a is electrically connected to theopen-loop and/or closed-loop control unit 60 a. The locking unit 24 a iselectrically connected to the drive unit 16 a via the open-loop and/orclosed-loop control unit 60 a.

The locking unit 24 a has at least one timer function which is providedfor at least partially automatically triggering the maintaining of theactive operating mode as a function of an actuation period of theswitching element 14 a. The locking unit 24 a comprises at least oneelectronic timing element 62 a which makes available the timer function.However, the at least one timing element 62 a can also be embodiedmechanically and/or in some other way which appears appropriate to aperson skilled in the art. The timer function of the locking unit 24 ais provided for automatically triggering the maintaining of the activeoperating mode after the actuation period of the switching element 14 aof more than 10 seconds by the operator. It is also conceivable that thetimer function of the locking unit 24 a is provided for alreadyautomatically triggering the maintaining of the active operating modeafter the actuation period of the switching element 14 a of more than 5seconds by the operator. Alternatively, it is also conceivable that theactuation period of the switching element 14 a by the operator, whichperiod is necessary for automatically triggering the maintaining of theactive operating mode, is designed to be adjustable by the operator.After the operator keeps the switching element 14 a pressed for at least10 seconds, the maintaining of the active operating mode is triggeredautomatically by means of the open-loop and/or closed-loop control unit60 a.

After the triggering of the maintaining of the active operating mode bythe locking unit 24 a, the operator can use the hand-held power tool 10a independently of actuation of the switching element 14 a. In order todeactivate the maintaining of the active operating mode by the lockingunit 24 a, the operator presses, for example, the switching element 14 aagain. However, other configurations for deactivating the maintaining ofthe active operating mode by the locking unit 24 a, which appearappropriate to a person skilled in the art, such as, for example,actuating an additional switch-off element, are also conceivable.

FIGS. 3 to 6 show further exemplary embodiments of the disclosure. Thefollowing descriptions and the drawings are limited essentially to thedifferences between the exemplary embodiments, wherein reference canbasically also be made to the drawings and/or the description of theother exemplary embodiments, in particular of FIGS. 1 and 2, withrespect to identically designated components, in particular with respectto components with the same reference symbols. In order to differentiatethe exemplary embodiments, the letter a is appended to the referencenumbers of the exemplary embodiment in FIGS. 1 and 2. The letter a isreplaced by the letters b to d in the exemplary embodiments in FIGS. 3to 6.

FIG. 3 shows an alternative hand-held power tool 10 b. The hand-heldpower tool 10 b is formed by a hammer drill. However, otherconfigurations of the hand-held power tool 10 b which appear appropriateto a person skilled in the art, such as, for example, an impact drill,drilling machine, hand-held jigsaw, hand-held circular saw or anglegrinder. The hand-held power tool 10 b has a tool holder 48 b which isprovided for holding an insertion tool 20 b which can be embodied as adrill and/or chisel. The tool holder 48 b is formed by a quick-changetool holder 18 b. It is basically also conceivable for the tool holder48 b to be embodied, for example, as a drill chuck. The tool holder 48 bcorresponds at least essentially to the tool holder 48 b alreadydescribed. Furthermore, the hand-held power tool 10 b has at least onedrive unit 16 b. The hand-held power tool 10 b has a drive unit 16 bwhich comprises an electric motor 50 b and at least essentiallycorresponds to the drive unit 16 a already described. In addition, thehand-held power tool 10 b has a transmission unit 52 b and a drivedevice 54 b having a percussion mechanism 34 b. The transmission unit 52b and the drive device 54 b correspond to the transmission unit 52 aalready described and to the drive device 54 a already described.

In order to supply the hand-held power tool 10 b with electrical power,the hand-held power tool 10 b has an accumulator interface 22 b which isprovided for coupling the hand-held power tool 10 b to a hand-held powertool accumulator pack 64 b. The accumulator interface 22 b is providedfor electrically and mechanically coupling the hand-held power toolaccumulator pack 64 b to the hand-held power tool 10 b. The accumulatorinterface 22 b of the hand-held power tool 10 b is provided forreplaceably attaching the hand-held power tool accumulator pack 64 b.FIG. 3 shows the hand-held power tool 10 b and the hand-held power toolaccumulator pack 64 b in a state in which it is coupled to the hand-heldpower tool 10 b by means of the accumulator interface 22 b.

The hand-held power tool 10 b additionally has at least one switchdevice 12 b which comprises at least one switching element 14 b at leastfor activating a power supply of the drive unit 16. The hand-held powertool 10 b has a switch device 12 b which comprises a switching element14 b for activating the electric motor 50 b of the drive unit 16 b. Theswitch device 12 b and the switching element 14 b correspond to theswitch device 12 a already described and to the switching element 14 aalready described. In order to activate the electric motor 50 b of thedrive unit 16 b, the operator of the hand-held power tool 10 b pressesthe switching element 14 b and therefore places the hand-held power tool10 b in an active operating mode. In order to maintain this activeoperating mode, the operator keeps the switching element 14 b pressed.

The switch device 12 b also comprises at least one locking unit 24 bwhich is provided for maintaining the active operating mode at leastessentially independently of an effect of an operator actuating force,which operating mode can be activated by actuating the switching element14 b. The locking unit 24 b corresponds to the locking unit 24 a alreadydescribed. The locking unit 24 b is embodied as an electronic lockingunit. The hand-held power tool 10 b additionally has at least oneopen-loop and/or closed-loop control unit 60 b which is provided forperforming open-loop and/or closed-loop control at least of the electricmotor 50 b of the drive unit 16 b. The locking unit 24 b is electricallyconnected to the open-loop and/or closed-loop control unit 60 b. Thelocking unit 24 b is electrically connected to the drive unit 16 b viathe open-loop and/or closed-loop control unit 60 b.

The locking unit 24 b comprises at least one acoustic pick-up element 26b which is provided at least for picking up at least one acousticcharacteristic variable, wherein the locking unit 24 b is provided forperforming open-loop and/or closed-loop control of the maintaining of anactive operating mode as a function of the at least one detectedacoustic characteristic variable. The locking unit 24 b comprises anacoustic pick-up element 26 b. The acoustic pick-up element 26 b isprovided for picking up an acoustic characteristic variable. Theacoustic pick-up element 26 b is provided for picking up at least onevoice command of the operator of the hand-held power tool 10 b. Theacoustic pick-up element 26 b is embodied as a voice-recognition module.The operator of the electric hand-held power tool 10 b can maintain theactive operating state by means of a voice command which is picked upand detected by the acoustic pick-up element 26 b. The acoustic pick-upelement 26 b is coupled to the open-loop and/or closed-loop control unit60 b and, after the picking up and recognition of the voice command ofthe operator of the hand-held power tool 10 b, passes on an electricalsignal to the open-loop and/or closed-loop control unit 60 b. Theopen-loop and/or closed-loop control unit 60 b activates the maintainingof the active operating mode as a function of this electrical signal. Inorder to deactivate the maintaining of the active operating mode, theoperator of the hand-held power tool 10 b outputs a further voicecommand which is picked up and detected by the acoustic pick-up element26 b. Alternatively or additionally, manual deactivation of themaintaining of the active operating mode is also conceivable, forexample, by means of a deactivation switching element.

The hand-held power tool 10 b also has at least one sensor unit 30 bwhich is provided at least for picking up at least one safetycharacteristic variable for picking up a fault, wherein the locking unit24 b is provided for automatically switching off the drive unit 16 b asa function of the picked-up safety characteristic variable or forreducing a rotational speed and/or a power of the drive unit 16 b. Thehand-held power tool 10 b comprises a sensor unit 30 b for picking up atleast one safety characteristic variable for picking up the fault. Thesensor unit 30 b comprises at least one sensor element 66 b which isprovided for picking up the safety characteristic variable. The sensorelement 66 b is formed via an acceleration sensor. The safetycharacteristic variable is formed by an acceleration of the hand-heldpower tool 10 b about a machining axis 68 b of the insertion tool 20 bof the hand-held power tool 10 b. If the value of the safetycharacteristic variable reaches or exceeds a defined limiting value, thesensor unit 30 b detects a fault. The fault is caused, for example, bythe insertion tool 20 b becoming stuck in an active operating state in aworkpiece and becoming blocked, as a result of which, the hand-heldpower tool 10 b is accelerated in an uncontrolled fashion about themachining axis 68 b of the insertion tool 20 b. The sensor unit 30 b iscoupled to the locking unit 24 b and, after the detection of the fault,passes on an electrical signal to the locking unit 24 b. The lockingunit 24 b is provided for switching off the drive unit 16 b as afunction of the electrical signal, independently of activatedmaintaining of the active operating state. It is also conceivable that afirst limiting value of the safety characteristic variable is defined,the reaching or exceeding of the value of which safety characteristicvariable causes the rotational speed or the power of the drive unit 16 bto be reduced, and in that additionally a further limiting value of thesafety characteristic variable is defined, the reaching or exceeding ofwhich safety characteristic variable causes the rotational speed or thepower of the drive unit 16 b to be switched off. The further limitingvalue of the safety characteristic variable is higher here than thefirst limiting value of the safety characteristic variable.

FIGS. 5 and 6 are schematic illustrations of a further embodiment of ahand-held power tool 10 c and of a circuit of the hand-held power tool10 c. The hand-held power tool 10 c corresponds to the hand-held powertool 10 a which has already been described, and comprises a tool holder48 c which is embodied as a quick-change tool holder 18 c. The hand-heldpower tool 10 c has a drive device 54 c with a percussion mechanism 34 cwhich corresponds to the percussion mechanism 34 a already described.The hand-held power tool 10 c has at least one switch device 12 c whichcomprises at least one switching element 14 c at least for activating apower supply of a drive unit 16 c. The hand-held power tool 10 c has aswitch device 12 c which comprises a switching element 14 c foractivating an electric motor 50 c of the drive unit 16 c. The switchdevice 12 c and the switching element 14 c correspond to the switchdevice 12 a already described and to the switching element 14 a alreadydescribed. In order to activate the electric motor 50 c of the driveunit 16 c, the operator of the hand-held power tool 10 c presses theswitching element 14 c and therefore places the hand-held power tool 10c in an active operating mode. In order to maintain this activeoperating mode, the operator keeps the switching element 14 c pressed.

The switch device 12 c also comprises at least one locking unit 24 cwhich is provided at least essentially independently of an effect of anoperator actuating force for maintaining the active operating mode whichcan be activated by actuating the switching element 14 c. The lockingunit 24 c corresponds to the locking unit 24 a which has already beendescribed. The locking unit 24 c is embodied as an electronic lockingunit. The hand-held power tool 10 c also has at least one open-loopand/or closed-loop control unit 60 c which is provided for performingopen-loop and/or closed-loop control of at least the electric motor 50 cof the drive unit 16 c. The locking unit 24 c is electrically connectedto the open-loop and/or closed-loop control unit 60 c. The locking unit24 c is electrically connected to the drive unit 16 c via the open-loopand/or closed-loop control unit 60 c. The locking unit 24 c has at leastone pick-up element 28 c for picking up a movement characteristicvariable of the operator, wherein the locking unit 24 c is provided forperforming open-loop and/or closed-loop control of the maintaining of anactive operating mode as a function of the at least one picked-upmovement characteristic variable. The locking unit 24 c has the pick-upelement 28 c for picking up a movement characteristic variable of theoperator of the hand-held power tool 10 c. The locking unit 24 c isprovided for performing open-loop and/or closed-loop control of themaintaining of the active operating mode as a function of the picked-upmovement characteristic variable. The pick-up element 28 c is at leastprovided for optically picking up the movement characteristic variableof the operator. The pick-up element 28 c is at least partially formedby a camera. The pick-up element 28 c is provided for picking up andevaluating the movement characteristic variable of the operator. Theoperator of the hand-held power tool 10 c can maintain the activeoperating state by means of a gesture, for example a movement of thehand, which is picked up and recognized by the pick-up element 28 c. Thepick-up element 28 c is coupled to the open-loop and/or closed-loopcontrol unit 60 c and, after the picking up and recognition of thegesture of the operator of the hand-held power tool 10 c, passes on anelectrical signal to the open-loop and/or closed-loop control unit 60 c.The open-loop and/or closed-loop control unit 60 c activates themaintaining of the active operating mode as a function of thiselectrical signal. In order to deactivate the maintaining of the activeoperating mode, the operator of the hand-held power tool 10 c carriesout a further gesture which is picked up and detected by the pick-upelement 28 c. Alternatively or additionally, manual deactivation of themaintaining of the active operator is conceivable, for example by meansof a deactivation switching element.

FIGS. 7 and 8 are a schematic illustration of a further exemplaryembodiment of a hand-held power tool 10 d and of a circuit of thehand-held power tool 10 d. The hand-held power tool 10 d corresponds tothe hand-held power tool 10 a already described and comprises a toolholder 48 d which is embodied as a quick-change tool holder 18 d. Thehand-held power tool 10 d has a power take-off device 54 d with apercussion mechanism 34 d which corresponds to the percussion mechanism34 a which has already been described. The hand-held power tool 10 d hasat least one switch device 12 d which comprises at least one switchingelement 14 d at least for activating a power supply of a drive unit 16d. The hand-held power tool 10 d has a switch device 12 d whichcomprises a switching element 14 d for activating an electric motor 50 dof the drive unit 16 d. The switch device 12 d and the switching element14 d correspond to the switch device 12 a already described and to theswitching element 14 a already described. In order to activate theelectric motor 50 d of the drive unit 16 d, the operator of thehand-held power tool 10 d presses the switching element 14 d andtherefore places the hand-held power tool 10 d in an active operatingmode. In order to maintain this active operating mode, the operatorkeeps the switching element 14 d pressed.

The switching device 12 d also comprises at least one locking unit 24 dwhich is provided for maintaining the active operating mode at leastessentially independently of an effect of an operator actuating force,which operating mode can be activated by actuating the switching element14 d. The locking unit 24 d corresponds to the locking unit 24 a alreadydescribed. The locking unit 24 d is embodied as an electronic lockingunit. The hand-held power tool 10 d also has at least one open-loopand/or closed-loop control unit 60 d which is provided for performingopen-loop and/or closed-loop control at least of the electric motor 50 dof the drive unit 16 d. The locking unit 24 d is electrically connectedto the open-loop and/or closed-loop control unit 60 d. The locking unit24 d is electrically connected to the drive unit 16 d via the open-loopand/or closed-loop control unit 60 d.

The hand-held power tool 10 d also comprises at least one sensor unitwhich has at least one pressure sensor 32 d for picking up at least onepressing force, wherein the locking unit 24 d is provided formaintaining an active operating mode as a function of the picked-uppressing force. The hand-held power tool 10 d comprises a sensor unit 30d. The sensor unit 30 d has a pressure sensor 32 d for picking up apressing force. The pressure sensor 32 d is formed by a force pick-up.The pressure sensor 32 d is formed by piezo-force pick-up. However,other configurations of the pressure sensor 32 d which appearappropriate to a person skilled in the art, such as, for example, aspring body force pick-up, are conceivable. When a workpiece ismachined, the operator presses, with the pressing force, the hand-heldpower tool 10 d with an insertion tool against the workpiece along amachining axis of the insertion tool. If a value of the pressing forcereaches or exceeds a predefined limiting value, the sensor unit 30 dpasses on an electrical signal to the locking unit 24 d, by means ofwhich electrical signal activation of the active operating state isenabled. Activation of the active operating state is possible only if avalue of the pressing force reaches or exceeds the defined limitingvalue and the electrical signal is passed on to the locking unit 24 d.If the value of the pressing force drops below the defined limitingvalue in an active operating state which is maintained by means of thelocking unit 24 d, the maintaining of the active operating state isinterrupted. The maintaining of the active operating state isinterrupted if the value of the pressing force drops below the definedlimiting value over a time period of 10 seconds. However, other timeperiods which appear appropriate to a person skilled in the art or atime period which can be set and varied by a person skilled in the artare also conceivable. As result it is possible to ensure that thehand-held power tool 10 d is automatically switched off after being putdown in an active operating state by the operator.

The sensor unit 30 d of the hand-held power tool 10 d additionallycomprises at least one frequency sensor 36 d which is provided forpicking up an impact frequency of the percussion mechanism 34 d, whereinthe locking unit 24 d is provided for performing open-loop and/orclosed-loop control of the maintaining of the active operating mode as afunction of the picked-up impact frequency. The sensor unit 30 dcomprises a frequency sensor 36 d for picking up the impact frequency ofthe percussion mechanism 34 d. The frequency sensor 36 d is embodied asan acceleration sensor or in some other way which appears appropriate toa person skilled in the art. The frequency sensor 36 d is provided forpicking up an idle stroke of the percussion mechanism 34 d in an activeoperating state. If the frequency sensor 36 d picks up a plurality ofsuccessive idle strokes of the percussion mechanism 34 d while themaintaining of the active operating state is activated by the lockingunit 24 d, the maintaining of the active state is interrupted. Themaintaining of the active operating state is interrupted after thepicking up of 10 idle strokes. However, a different number of idlestrokes which appears appropriate to a person skilled in the art or anumber of idle strokes which can be set and varied by the operator isalso conceivable.

The hand-held power tool 10 d also comprises at least one communicationunit 38 d for communicating with an external device 40 d, wherein thelocking unit 24 d is provided for performing open-loop and/orclosed-loop control of the active operating mode as a function of acommunication between the communication unit 38 d and the externaldevice 40 d. The hand-held power tool 10 d has the communication unit 38d for communicating with the external device 40 d. The external device40 d is formed by a Smartphone or a table. However, other configurationsof the external device 40 d which appear appropriate to a person skilledin the art are conceivable. The external device 40 d and thecommunication unit 38 d of the hand-held power tool 10 d communicatewith one another in a wireless fashion. The external device 40 d and thecommunication unit 38 d of the hand-held power tool 10 d communicatewith one another via WLAN. However, other configurations of thecommunication which appear appropriate to a person skilled in the art,such as, for example, via Bluetooth or infrared, are also conceivable.An app is installed in advance for this on the external device 40 d. Bymeans of a user interface of the app, the operator can control thelocking unit 24 d of the hand-held power tool 10 d from the externaldevice 40 d. The communication unit 38 d is electronically connected tothe open-loop and/or closed-loop control unit 60 d. The operator cantherefore activate the maintaining of the active operating state of theheld-held power tool 10 d by means of the external device 40 d.Alternatively or additionally, the operator can deactivate themaintaining of the active operating state by means of the externaldevice 40 d. In addition it is conceivable that the operator can use theexternal device 40 d to set open-loop and/or closed-loop controlvariables of the hand-held power tool 10 d, such as, for example, thenumber of idle strokes for the frequency sensor 36 d, to set the timeperiod for the pressure sensor 32 c and/or at least one othercharacteristic variable which appears to be appropriate to a personskilled in the art.

FIG. 9 shows a flowchart of a method relating to operation of thehand-held power tool 10 b. The method is, for the sake of simplicity,described on the basis of the hand-held power tool 10 b illustrated inFIGS. 3 and 4. However, the method is also valid for the other exemplaryembodiments of the inventive hand-held power tool which are shown inFIGS. 1 and 2, and 5 or 6, respectively. The method has at least onemethod step 42 in which the operator activates the active operating modeby actuating the switching element 14 b. The operator activates theactive operating state by pressing the switching element 14 b. Themethod has at least one further method step 44 in which the locking unit24 b maintains the active operating mode independently of the actuationof the switching element 14 b by the operator. The locking unit 24 b isactuated, and the active operating mode is maintained, in the wayalready described above. The method comprises at least one furthermethod step 46 in which a fault is detected, and the active operatingmode which is maintained by means of the locking unit 24 b isdeactivated automatically as a function of the detected fault. The faultis detected by means of the sensor unit 30 b of the hand-held power tool10 b which is provided for picking up the safety characteristicvariable. The method can also comprise at least one further method step70 in which at least one further open-loop and/or closed-loop controlvariable, such as, for example, the pressing force and/or the impactfrequency, is picked up and evaluated.

What is claimed is:
 1. A hand-held power tool comprising: a drive unithaving a power supply; at least one switch device comprising: at leastone switching element configured to activate an active operating mode ofthe power supply of the drive unit in response to an initial operatoractivation force; and at least one locking unit configured to maintainthe active operating mode independently of an instantaneous operatoractivation force on the at least one switching element; and at least oneof: at least one quick-change tool holder configured to hold aninsertion tool with a shaft that has a maximum transverse extent ofgreater than 10 mm; and at least one accumulator interface, wherein: theat least one locking unit includes at least one pick-up elementconfigured to pick up a movement characteristic variable of an operator;and the at least one locking unit is configured to perform at least oneof open-loop control and closed-loop control of the maintaining of theactive operating mode as a function of the at least one movementcharacteristic variable.
 2. The hand-held power tool according to claim1, wherein the at least one locking unit is configured with at least onetimer function configured to at least partially automatically triggerthe maintaining of the active operating mode as a function of anactuation period of the at least one switching element.
 3. The hand-heldpower tool according to claim 1, wherein: the at least one locking unitincludes at least one acoustic pick-up element configured to pick up atleast one acoustic characteristic variable; and the at least one lockingunit is configured to perform at least one of open-loop control andclosed-loop control of the maintaining of the active operating mode as afunction of the at least one acoustic characteristic variable.
 4. Thehand-held power tool according to claim 1, further comprising: at leastone sensor unit configured to pick up a fault by picking up at least onesafety characteristic variable; and wherein the at least one lockingunit is configured to, as a function of the at least one safetycharacteristic variable, at least one of automatically switch off thedrive unit, reduce a rotational speed of the drive unit, and reduce apower level of the drive unit.
 5. The hand-held power tool according toclaim 1, further comprising: at least one sensor unit having at leastone pressure sensor configured to pick up at least one pressing force,wherein the at least one locking unit is configured to maintain theactive operating mode as a function of the at least one pressing force.6. The hand-held power tool according to claim 1, further comprising: atleast one percussion mechanism; and at least one sensor unit includingat least one frequency sensor configured to pick up an impact frequencyof the at least one percussion mechanism, wherein the at least onelocking unit is configured to perform at least one of open-loop controland closed-loop control of the maintaining of the active operating modeas a function of the impact frequency.
 7. The hand-held power toolaccording to claim 1, further comprising: at least one communicationunit configured to communicate with an external device, wherein the atleast one locking unit is configured to perform at least one ofopen-loop control and closed-loop control of the maintaining of theactive operating mode as a function of a communication between thecommunication unit and the external device.
 8. The hand-held power toolaccording to claim 1, further comprising: a control unit configured tooperate the at least one switching element to: activate the activeoperating mode of the power supply in response to the initial operatoractivation force; and maintain, with the at least one locking unit, theactive operating mode independently of the instantaneous operatoractivation force.
 9. The hand-held power tool according to claim 8, thecontrol unit further configured to: detect a fault; and automaticallydeactivate the active operating mode as a function of the detectedfault.
 10. The hand-held power tool according to claim 1, wherein thepick-up unit is an optical pick-up unit.
 11. The hand-held power toolaccording to claim 10, wherein the locking unit is configured tomaintain the active operating mode in response to detection of anoperator gesture by the pick-up unit.
 12. The hand-held power toolaccording to claim 11, wherein the locking unit is further configured todeactivate the active operating mode in response to detection of afurther operator gesture.
 13. A method for operating the hand-held powertool including (i) a drive unit having a power supply, (ii) at least oneswitch device, and (iii) at least one of (a) at least one quick-changetool holder configured to hold an insertion tool with a shaft that has amaximum transverse extent of greater than 10 mm and (b) at least oneaccumulator interface, the method comprising: activating an activeoperating mode in response to an initial operator activation force by anoperator on at least one switching element of the at least switch deviceof the hand-held power tool; and maintaining, with at least one lockingunit of the at least switch device of the hand-held power tool, theactive operating mode independently of an instantaneous operatoractuation force by the operator on the at least one switching element;picking up a movement characteristic variable of an operator with atleast one pick-up element of the at least one locking unit; andperforming, with the at least one locking unit, at least one ofopen-loop control and closed-loop control of the maintaining of theactive operating mode as a function of the at least one movementcharacteristic variable.
 14. The method according to claim 13, furthercomprising: picking up a fault; and automatically deactivating theactive operating mode as a function of the picked up fault.
 15. Ahand-held power tool comprising: a drive unit having a power supply; atleast one switch device comprising: at least one switching elementconfigured to activate an active operating mode of the power supply ofthe drive unit in response to an initial operator activation force; andat least one locking unit; a control unit configured to operate the atleast one locking unit to maintain the active operating modeindependently of an instantaneous operator activation force on the atleast one switching element; and at least one of: at least onequick-change tool holder configured to hold an insertion tool with ashaft that has a maximum transverse extent of greater than 10 mm; and atleast one accumulator interface, wherein the at least one locking unitincludes at least one pick-up element configured to pick up a movementcharacteristic variable of an operator; and the control unit isconfigured to perform at least one of open-loop control and closed-loopcontrol of the maintaining of the active operating mode as a function ofthe at least one movement characteristic variable.
 16. The hand-heldpower tool according to claim 15, wherein the pick-up unit is an opticalpick-up unit.
 17. The hand-held power tool according to claim 16,wherein the control unit is configured to maintain the active operatingmode in response to detection of an operator gesture by the pick-upunit.
 18. The hand-held power tool according to claim 17, wherein thecontrol unit is further configured to deactivate the active operatingmode in response to detection of a further operator gesture.